 var x = document.getElementById("myHeader")  /* 获取DOM元素，生成Bom对象，对象x === window.x*/
console.log(x.innerHTML)  // 测试方法：alert console.log
var nameDiv = document.getElementById('name');
console.log(nameDiv.innerHTML)

nameDiv.innerHTML = 'test innerHTML'
console.log(nameDiv.innerHTML)